Chris: My default player (totem in Ubuntu) played it fine, but when I tried to load it into Audacity (to confirm my suspicion that the right channel is louder than the left), it went berserk. However, once I renamed the file to end in .wav instead of .mp3, Audacity was perfectly happy with it (and did indeed confirm said suspicion). Perhaps your player will play it too if you rename it.

For a sound test it would be good to have more contrasting dynamics, you seem to be playing this at a healthy forte throughout. If in fact your actual playing level was softer, then your recording sensitivity is set too high. The level probably needs to come down even if you were playing f, because if you play ff, you will probably over-drive the recorder, causing clipping.

If you are trying to evaluate your recording setup, it might help if you told us a bit about it, like where the microphone(s) is/are in relation to the piano. Is it different from how it was for the Beethoven sample?

Certain notes come out more prominently than others, one in particular: the Ab below middle C, most evident in the first 5 bars of the 2nd repeated section.

Your recording cuts off the first note of the piece, and cuts short the last note. You want a bit of (natural, not artificial) silence before you begin and after the last note dies out.

I'm sure it will, most players go by the name rather than the contents to determine the type. But this is not the point here. It should be in mp3 format.

Indeed. I only mentioned it because you had said that you "can't" play it.

my piano was worked on again and some more adjustments were made. Perhaps I'll get to recording some more things when I have the time.